South African model Gabriella Engels, allegedly assaulted by Zimbabwe First Lady Grace Mugabe, looks on during a press conference at the civil rights organization AfriForum on Thursday.

A 20-year old South African model accusing Zimbabwean First Lady Grace Mugabe of beating her with an extension cord has rejected a proposed cash settlement, according to her legal team.

Mugabe's whereabouts are unknown, and South African Police Minister Fikile Mbalula told reporters that the country implemented a "red alert" for her at its borders. "She is not somebody who has been running away," Mbalula said, according to South Africa's News24.

The first lady, wife of Zimbabwean President Robert Mugabe, "failed to turn herself in to South African authorities Tuesday," NPR's Colin Dwyer reported. Mugabe allegedly assaulted Gabriella Engels at a Johannesburg hotel in the presence of her body guards, and her two sons were reportedly in a nearby room, Colin added.

"On Wednesday, the government of Zimbabwe requested diplomatic immunity for Mugabe, saying she was in South Africa for a regional summit," reporter Peter Granitz tells our Newscast unit. "But the victim's lawyers said she was in the country for personal reasons, including shopping and medical treatment, and that means she would not qualify for the immunity."

Engels' legal team said that an unnamed third party "offered to settle the case out of court for an undisclosed amount of money," which she has rejected, Granitz added.

Engels appeared at a press conference Thursday with a large white bandage on her forehead. "One feels powerless if you are the victim of violence by a person like Mrs Mugabe, who occupies a position of power," she said, according to the advocacy group representing her.

Her lawyer Gerrie Nel, who is known for winning a murder conviction against Paralympic athlete Oscar Pistorius, said "no one, not even Mrs Grace Mugabe, must be allowed to bypass the law as a result of their position of power." He vowed to pursue private prosecution if the National Prosecuting Authority "fail to prosecute Mrs. Mugabe without good cause."

Should Mugabe be granted diplomatic immunity, the organization representing Engels says it is "prepared to fight this in the highest court."

A police official told Reuters that authorities have not yet issued an arrest warrant because they are still considering Mugabe's request for diplomatic immunity.

The situation is delicate diplomatically and politically. South Africa's primary opposition group is pressuring President Jacob Zuma to make sure Mugabe doesn't leave, The Associated Press reported.

Robert Mugabe – the world's oldest sitting president – arrived in South Africa Wednesday evening. Zimbabwe's Herald newspaper says he is there for a regional summit and does not mention his wife's legal troubles. Other news outlets suggest the leader is there at least partially to manage the crisis.

According to Reuters, "the South African government has made no official comment on the case and foreign ministry spokesmen have not answered their phones for two days but the issue is causing waves at the highest level."

This isn't the first time that the Zimbabwean first lady has faced accusations of assault. The AP says several prior alleged incidents include "a 2009 visit to Hong Kong in which a photographer accused her of beating him up."

Grace Mugabe is seen as a possible successor to her aging husband. Nel has said that a conviction could result in jail time, according to the AP.